Advanced Infrastructure Penetration Testing
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Risk analysis

The main role of an information security professional is to evaluate risks against enterprise assets (resources that need protection) and implement security controls to defend against those risks. Analyzing risks is a very important skill because good judgment will make us select the best security controls and protection mechanisms, including the amount of financial resources needed for the deployment of these safeguards. In other words, a bad decision will cost the enterprise a huge amount of money and even worse, the loss of customers' data. We can't calculate the risk in a quantitative way without knowing the threats and vulnerabilities. A threat is a potential danger to our assets that could harm the systems. A vulnerability is a weakness that allows the threat to take negative actions. These two terms and the connection between them is described by the formula Risk = Threat*Vulnerability.

To evaluate the threat and the vulnerability, you need to assign a number in a range of one to five, for example. Using another range is possible. Sometimes, we can add another factor named impact, which describes the impact of the damage caused. In other cases, it is expressed as an amount of money to describe the cost of that impact, so the formula could be expressed as Risk = Threat*Vulnerability*Impact.

To perform a qualitative and quantitative risk analysis, we may use the risk analysis matrix according to the Australia/New Zealand 4360 Standard ( AS/NZS 4360) on risk management. 

The information security professional needs to classify risks based on two metrics: the frequency of occurrence and the severity of accident. The results of this classification will dictate the next action plan. Thus, if the risks are high, they must notify senior management. The next step is to create a roadmap to downgrade every risk to low, as much as possible, as shown here: